As discussed in U.S. Pat. No. 5,288,007, issued to Mario J. Interrante et al. and assigned to the present assignee, the disclosure of which is incorporated herein by reference, the constant strive for increased circuit density on chips and modules has resulted in ever smaller electrical lines and circuit pads. The increased density and level of integration also have increased the probability that the electrical lines or circuit pathways may have to be rerouted after manufacture in order that the chips and modules be made free from defects, which are typically discovered during chip or module burn in or testing. It has become uneconomical simply to isolate or discard defective portions of a large scale integration (LSI) package because of the expensive manufacturing investments involved. The rerouting of circuit wires is done for a variety of reasons. One important reason, other than defect correction, is to customize a part for a particular performance requirement. Other reasons are discussed in the aforementioned patent.
The establishment of a post-manufacturing electrical connection between circuit pads for any of the foregoing reasons requires, of course, that the new connection itself be free of defects and that it be accomplished without disturbing the pre-existing sound circuits. To the end that defects in the new circuit connection be avoided, U.S. Pat. No. 5,288,007 also teaches that both ends of the new connection wire be established simultaneously with the respective circuit pads so that the establishment of a later pad bond does not deleteriously impact an earlier pad bond as is sometimes the case where the two ends of a single connection wire are bonded sequentially to respective pads.
Although the simultaneous connection technique was an important step forward, other problems remain to be solved. In particular, there is the problem of how to supply, handle and position the very fine wire that must be used in accomplishing the interconnecting of closely spaced circuit pads of very small areas.